JPS60182867A - Paper medium information recording synchronizing system - Google Patents

Abstract

PURPOSE:To obtain a recording synchronism system possible for transmission/ reception independently of the difference in the resolution between the transmission side and reception side by reading an information bit detecting mark changed in the same size and in stripe as one bit of the transmission side picture information before start of scanning and transmitting the result. CONSTITUTION:When a picture data corresponding to a scanning line 3a is given to a CPU13 and a pattern having alternately black and white levels appears, the CUP13 recognizes that the scanning of the information bit detecting mark is started, the center position of the main scanning at each information bit is obtained and stored in a memory 14a. When a picture data corresponding to a scanning line 3b is given to the CPU13, the CPU13 recognizes the start of picture data and the picture data is stored sequentially in a memory 14b. Then the center position in the sub-scanning direction is obtained from the picture data stored in the memory 14b, the center point of each information bit is obtained from the center position in the main scanning direction stored in a memory 13 and logical ''1'' or ''0'' of each information bit is restored from the main scanning line passing through the center point.

Description

DETAILED DESCRIPTION OF THE INVENTION (al) Technical Field of the Invention The present invention relates to a method for recording image information of a bit image on paper, and in particular to a method for recording image information of a document read by a scanner.
The present invention relates to a method capable of restoring data regardless of the resolution of a receiver.

(bl Conventional technology and problems) Conventionally, the technologies for recording information on paper and reading it out with a scanner to restore the information include OMR, barcode, and OC.
R etc. have been put into practical use. However, these methods can only record a small amount of information on a single sheet of paper. - The method of recording information on paper can be reproduced in large quantities and at low cost using copying machines and printing machines, and is a method of digitally recording information on paper using magnetic destructive technology. has been announced.

This is also known as Paper Pulse Code Mod
ulation (hereinafter abbreviated as PPCM).

Since the gradation characteristics of FAX machines and copying machines are generally poor, one bit of image data (hereinafter abbreviated as information bit) is recorded in binary black and white without using halftones. In other words, white is “
1", black is recorded as "θ", and when it occurs repeatedly, the threshold is set at the center between white and black, and it is recorded as "1" or "0" depending on whether it is closer to white or black.
Make a judgment.

FIG. 1 shows an explanatory diagram of the principle of PPCM.

In the figure, the black and white striped pattern shows an example of a state in which 8-bit image data 10110110 is recorded on paper, and the dimensions W and d shown in the figure indicate the size of the information bit area. , represents the height W in the sub-scanning direction and the width d in the main scanning direction. The height W and width d are selected to be sufficiently larger than the resolution of the transmitter and receiver used. Here, the height W is 4 scanning lines and the width d is 8 pixels. A frame indicated by a broken line in the inner recess is a line indicating an area in which information is in focus, and is not actually recorded.

FIG. 2 shows an explanatory diagram of the two-dimensional start-stop synchronization method.

In the figure, 1 is the edge of the paper (original), 2 is the scanning area boundary,
3 is the scanning line, 4 is the start bit detection mark, ■ ~ 0
each indicates a position on the scanning line.

The resolution of the facsimile machine that reads this document in the main scanning direction is 8 pixels/am, and the resolution in the sub-scanning direction is 3.85 pixels/am.
is used. The start bit detection mark 4 is a black line having the same size as the width d of the information bit and is recorded in advance from the upper left edge of the document to the lower edge of the document along the sub-scanning direction.

The PPCM synchronization method uses start-stop synchronization,
Scan the page as shown in scanning line 3, and when the start bit detection mark (black) is detected at ■, scan the width d/2. The point ■ that has advanced by a height w/2 in the sub-scanning direction is set as the center of the star 1-bit of the image data in the first main scanning direction, and is hereinafter referred to as an information bit that has advanced by a width d in the main scanning direction from ■. Information bits “1” and “0” from “white” and “black” of successive data at the positions of points ■, ■, ■, etc.
” was decided.

Next, the readout line for the information bits on the second grain is a width d/2 from point ■ when the scanning line passing through point ■ which has advanced by the height W in the sub-scanning direction detects the start bit detection mark.
Positioning is performed in the same way as for the first successive line, using point 0, which is advanced by 0, as the starting position.

However, in reality, when copying or printing paper on which information is recorded and distributing it, it is conceivable that devices with various different resolutions are used on the sending side and the receiving side. For this reason, if the height W and width d are determined in advance, the actual values must be selected from the combination of resolutions of the transmitting device and the receiving device, resulting in a very complicated process.

tel Purpose of the Invention In view of the above-mentioned conventional drawbacks, the present invention provides a recording synchronization method that can read information recorded on paper without considering the difference in resolution between the transmitting device and the receiving device in an image transmission device. The purpose is to provide.

(d+ Structure and object of the invention According to the present invention, there is provided a transmitting device that samples an image of a document and transmits the read image information, and a receiving device that receives the image information and records the image on a sheet of paper. In the image transmission device, the transmitting side prints an information bit detection mark that changes in stripes with the same size as one bit of the image information before reading out the document in the main scanning direction and the sub-scanning direction. This is achieved by providing a paper medium information recording synchronization system characterized in that the receiving side detects the size and position of each bit of received image information using the information focus detection mark.

(el　Embodiments of the invention Embodiments of the present invention will be described in detail below with reference to the drawings.

In the inner concave portions corresponding to those in FIGS. 1 and 2 are designated by the same reference numerals, and redundant explanation thereof will be omitted.

FIG. 3 is an explanatory diagram illustrating a recording synchronization method that is better than the conventional method based on the OMR sheet.

In the figure, 48 is an information focus detection mark in the main scanning direction;
4b indicates a start bit detection mark in the sub-scanning direction.

In paper medium information recording, in order to increase the recording density, it is preferable that the height W and width d of the information bit be at least twice the resolution on the reading side and as small as possible.

Therefore, when recording using the method shown in FIG. 3, the width d in the main scanning direction is too large compared to the height W in the sub-scanning direction, so the size of the information bit also becomes larger than the width d, making it impossible to increase the recording density. do not have.

FIG. 4 shows an explanatory diagram of the paper medium information recording synchronization method according to the present invention.

In the present invention, as an information bit detection mark, a striped pattern of the same size as the information bit and alternating black and white is placed on the first line in the main scanning direction starting from the upper left corner of the screen, as shown in the figure, before reading the image data. Information bit detection mark 5 in the main scanning direction to be added and information bit detection mark 5
An information bit detection mark 6 in the sub-scanning direction to be added to the first digit in the sub-scanning direction from the first digit to the bottom edge of the screen along the sub-scanning direction, that is, the first digit in the sub-scanning direction, is recorded in advance on the document.

In the figure, a reliable bit detection mark 6 has the same function as the start bit detection mark 4 shown in FIG. 3, and detects the first black bit in the sub-scanning direction by 6a.

The white bit in the next row is represented by 6b, and the rest are similarly represented by black 6c and white 6d.

FIG. 5 shows a block diagram of paper medium information reading according to the present invention.

In the figure, reference numeral 10 denotes a sheet of paper on which image information is recorded, which is read by a reading section 11 and passed as image data 21 to an information bit decoding section 12 for each scanning line. Information bit decoding unit 12
4. indicates the CPU 13 that inspects the image data and the center position in the main scanning direction for each information bit. It consists of a memory 14a for storing image data, an image memo 4b for storing image data, and an output terminal 22 for outputting decoded information bits.

The operation of FIG. 5 will be explained below with reference to the information focus detection mark of FIG. 4. When the image data corresponding to the scanning line 3a in FIG. 4 is passed to the CPU 13 and a pattern of alternating black and white appears, the CPU 13 uses this information to determine that scanning of the information bit detection mark preceding the image data has started. Knowing this, find the center position in the main scanning direction for each information bit (white, black) and record it in memo 1.4a. Leave it a.

Next, the image data corresponding to the scanning cotton 3b in FIG.
13, the black bit 6a of the information focus detection mark
Since the white bit changes to white bit 6b, the CPU 13 knows that scanning of the image data has started, and stores the image data sequentially in the image memo 4b.

The image data corresponding to scan &'j13c in Fig. 4 is cp
When passed to U13, the white bit 6b of the information bit detection mark changes to black bit 6c, so the CPU 13
It is known that the reading of information bits for a line has been completed.

Then, the center position in the sub-scanning direction is determined from the image data corresponding to the white bit 6b of the information bit detection mark stored in the image memory 14b, and the center position of each information bit is determined from this and the center position in the main scanning direction stored in the memory 14a. Find the center point,
"1" or "O" of each information bit is restored from the main scanning line passing through the center point.

Thereafter, the information focus is restored by repeating the positioning of subsequent information bits on the line in the same manner.

FIG. 6 is a diagram showing another embodiment of the present invention.

The difference between this figure and FIG. 4 is that the information bit detection mark has two lines in both the main scanning direction and the sub-scanning direction.
A checkered pattern is given.

In the figure, 7 is an information bit detection mark in the main scanning direction;
indicates an information bit detection mark in the sub-scanning direction. In this embodiment, when the size of the black and white dots recorded on the paper sheet differs depending on the printing characteristics of the printer, the position of the center point of each information focus is determined from the white and black information bit detection marks, and the position of the center point of each information bit is determined from the white and black information bit detection marks. Since the information bit detection mark can be regarded as a start bit and synchronization can be achieved, the accuracy of positioning can be improved.

In each of the embodiments described above, "1" and "0" are determined from the black and white of the center point pixel of each information bit, but in order to suppress noise on paper, majority decision logic It may also be determined using calculations such as.

If) Effects of the Invention As explained in detail above, according to the paper medium information recording synchronization method of the present invention, an information bit detection mark in an alternating black and white pattern of the same size as the information focus is given prior to the information bit. On the reading side, it is possible to detect the size of the information bits and the position of the information bits based only on the information recorded on the paper.

Furthermore, since the information bit detection marks are provided in the main scanning direction and the sub-scanning direction, it is possible to correct irregularities in the spacing of each pixel of the COD scanner of the reading device and uneven feeding in the sub-scanning direction.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the principle of PPCM, Figure 2 is an explanatory diagram of a two-dimensional wing synchronization method.3 Figure 3 is an explanatory diagram of a recording synchronization method that is better than the conventional method from the OM'R sheet. FIG. 4 is an explanatory diagram of a paper medium information recording synchronization system according to the present invention, FIG. 5 is a block diagram of a paper medium information reading section according to the present invention, and FIG. 6 is a diagram showing another embodiment of the present invention. In the figure, 5 and 7 indicate information bit detection marks in the main scanning direction, and 6, 6a to 6d, and 8 indicate information bit detection marks in the sub-scanning direction. Figure 1 $2 Figure 3 Figure i Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] In an image transmission device comprising a transmitting device that samples an image of a document and transmits image information read out, and a receiving device that receives the image information and records the image on paper, the transmitting side comprises: Prior to reading out the document in the main scanning direction and the sub-scanning direction, an information bit detection mark that changes in a stripe shape with the same size as one bit of the image information is read, and on the receiving side, the received image is detected by the information bit detection mark. A paper medium information recording synchronization method characterized by detecting the size and position of each bit of information.